/**
 * ClassName NullPointerExceptionTest
 * Description TODO
 * Author Hexiao
 * Date 2018/8/23 9:09
 * Version 1.0
 **/
public class NullPointerExceptionTest {
    private int age = 20;
    public static void main(String[] args) {
        NullPointerExceptionTest test = new NullPointerExceptionTest();
        test = null;
        System.out.println(test.age);//空指针异常
    }

}